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jacob_coda
17-Feb-2010, 22:41
Hello everyone! I am new here to the forum.

I am in the middle of restoring my second Graflex RB Super D and I have run into an issue that has me stumped. I thought I would try to pick everyone’s brains about a possible solution.

I have the camera back to about 90% of it’s full working potential, when I received it it was in several pieces after someone else had given up on trying to fix it. I think the solution to the problem may be fairly simple, but I feel like I am over thinking it, lol.

The problem is with the speed of the mirror returning to it’s up-right position after tripping the mirror release lever. On release the mirror does not return with enough force to trip the curtain release lever and complete the exposure. Instead it hangs up in-between the two releases and the exposure has to be completed by hand by pushing the curtain release lever. This problem occurs at all tension settings (H & L) and at all curtain aperture speeds (A,B,C,D). I have the sliding bar on the mirror setting lever locked down in the “I” position, and on release the mirror release lever does trip the automatic diaphragm mechanism. However it is immediately after that that the problem with the tension of the mirror returning occurs.

I had to repair the rear focal plane shutter curtain when I was putting the camera back together because it’s position on the top and bottom roller was not correct. When I would make an exposure with the camera the “slits” in the curtain would end up in the middle of the film back instead of the bottom, thus only giving 1/2 of an exposure. I hand rolled the curtain back to it’s correct position and adjusted the spring tension until I felt it was giving a correct exposure on release of the curtain release lever. Before I made these repairs I did not notice the problem with the mirror release tension, however the shutter curtain was only returning 1/2 of a full exposure as I noted before.

So my question is “Is there a way to easily adjust the tension of the (mirror return/curtain release lever) so that it has enough force to trip the curtain release lever by fully rotating it and completing the exposure?” I know that there is a round black access panel on the top left rear of the camera that is attached by 3 screws, it seems to be at the right height to be an access for the mirror spring mechanism, however I don’t want to take anything under tension apart until I have an idea of what I should be trying to adjust.

If anyone has any ideas that might help me come up with a solution I would greatly appreciate it. Thanks in advance for your time!

jnanian
18-Feb-2010, 07:29
hi jacob

i have a series d that had a similar problem when i first got it.
i ended up buying a parts hog and swapping out the shutter release lever ...
i remember also doing something with the spring, but it has been 10-15years and i don't
totally remember what i did. it was very easy though ...

you might pose this same question at graflex.org. they will be able to
help you without a doubt.

goodluck!
john

Bosaiya
18-Feb-2010, 13:12
I know that there is a round black access panel on the top left rear of the camera that is attached by 3 screws, it seems to be at the right height to be an access for the mirror spring mechanism, however I don’t want to take anything under tension apart until I have an idea of what I should be trying to adjust.

That's your ticket right there. Unscrew the three screws and try to turn the disc one full rotation clockwise. This will add some tension and keep the screw-holes lined up (sometimes they are not perfectly spaced). Re-attach the screws and try it. It should be snappier. If it's still not enough, repeat. There is a spring inside that is likely unsprung. Be careful not to go hog-wild as it can break the spring. But then it's just a little spring, you could make a new one out of a piece of wire if you had to.

There's a few guides online to overhauling old RBs, you should be able to find one without too much searching.

jacob_coda
18-Feb-2010, 14:47
That's your ticket right there. Unscrew the three screws and try to turn the disc one full rotation clockwise. This will add some tension and keep the screw-holes lined up (sometimes they are not perfectly spaced). Re-attach the screws and try it. It should be snappier. If it's still not enough, repeat. There is a spring inside that is likely unsprung. Be careful not to go hog-wild as it can break the spring. But then it's just a little spring, you could make a new one out of a piece of wire if you had to.

There's a few guides online to overhauling old RBs, you should be able to find one without too much searching.

Thanks,
That was it, however it did not fix the problem completely. The camera works perfectly on it's side but turning it upright causes the same problem to occur. I have the plate rotated as far as it can go but no dice. I think the weight of the mirror must be too much for the spring so I will try to replace it or rewind it to a higher tension.

Bosaiya
18-Feb-2010, 15:02
The little plate should be rotate quite a few times unless someone has already beaten you to that. Sounds like it might have finally given up the ghost, although unless the spring is actually broken I'd keep monkeying with it.

jacob_coda
20-Feb-2010, 18:56
The little plate should be rotate quite a few times unless someone has already beaten you to that. Sounds like it might have finally given up the ghost, although unless the spring is actually broken I'd keep monkeying with it.

You were right again! I decided to give it another shot this morning. I took the plate off re-connected the spring to both slots (it was backwards, left->right!) and hand rotated it clockwise until I could barely hold it down. I used a small jewelry hammer and some small brads to tack the plate into place so I could put the screws in the new guide holes. I pulled each brad out and replaced it with a screw one at a time. I flipped it over, flipped down the mirror...tripped the release...and...it worked like a charm. I spent the afternoon shooting some 400 tmax and 400nc (expired), hopefully the "shutter" speeds are close to correct, I guess I will find out in a few days...Thanks to everyone who responded!

Bosaiya
23-Feb-2010, 17:19
Glad I could be of assistance. I love those old cameras, maybe because even I can figure them out!